"It’s my first time with a man." "So, don’t blame me if this relationship doesn’t work out." Yeo Hanju, who confessed his love to Choi Chanyoung-sunbae, ended up becoming an unexplainable partner to Chanyoung. Although every day is filled with regret and humiliation, he can't stop his relationship with him. But then one day, Hanju unexpectedly got a stepmother and stepbrother. His stepbrother's name is Yoo Jihyeon. After that Hanju… 'I still regret that moment.'